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Hello, I lost the clutch side piston on my 94 V-max 500, it has happened twice, the prior owner and now me, when we took the machine appart we found that the air filter foam that is between the cab and the bottom of the guage cluster has been deteriorating and the bottom of the airbox had many small pieces of this foam in it. Could it be that the foam got sucked into the carb went into the engine and made some sort of a goo that destroyed the piston? Or maybe these foam particles made it into the carb and leaned out one of the jests that cause the incident twice in a row? My sled has 15000 kilometers on it. Any ideas???

Hello, I lost the clutch side piston on my 94 V-max 500, it has happened twice, the prior owner and now me, when we took the machine appart we found that the air filter foam that is between the cab and the bottom of the guage cluster has been deteriorating and the bottom of the airbox had many small pieces of this foam in it. Could it be that the foam got sucked into the carb went into the engine and made some sort of a goo that destroyed the piston? Or maybe these foam particles made it into the carb and leaned out one of the jests that cause the incident twice in a row? My sled has 15000 kilometers on it. Any ideas???

Rik...[/b]

I know exactly what is wrong! Your sled is old with a ton of miles. A 94 V-MAX 500 with 15,000 kilometers on it is toast. Thats like asking why a 1992 ford tempo with 350,000Km has a blown motor. You can't just change a piston there may be something wrong with the cylinder etc... There are many possiblities as to what the problem could be. Honestly the main problem is the sled is old. The motor probably needs to be completely rebuilt. If the air filters are old change them too. It is probably more worth while to buy a newer sled...

The clutch side is usually the first to go because of the extra heat comming from the clutch.

I know exactly what is wrong! Your sled is old with a ton of miles. A 94 V-MAX 500 with 15,000 kilometers on it is toast. Thats like asking why a 1992 ford tempo with 350,000Km has a blown motor. You can't just change a piston there may be something wrong with the cylinder etc... There are many possiblities as to what the problem could be. Honestly the main problem is the sled is old. The motor probably needs to be completely rebuilt. If the air filters are old change them too. It is probably more worth while to buy a newer sled...

The clutch side is usually the first to go because of the extra heat comming from the clutch.[/b]

Wow... what a constructive post. Glad there are people like you on these forums to "help" others.

__________________"Freedom is too precious to be held by the left hand"

how long between blow ups? can we see a pic of the piston? 15000km is alot but who cares. my dad has 16000km on his sx and still bullet proof. give us some pics and lets see if we cant figure out why it went down! oh yeah i forgot i have a 91 tempo with 351000 km and hasnt blown up lol

Hello, I lost the clutch side piston on my 94 V-max 500, it has happened twice, the prior owner and now me, when we took the machine appart we found that the air filter foam that is between the cab and the bottom of the guage cluster has been deteriorating and the bottom of the airbox had many small pieces of this foam in it. Could it be that the foam got sucked into the carb went into the engine and made some sort of a goo that destroyed the piston? Or maybe these foam particles made it into the carb and leaned out one of the jests that cause the incident twice in a row? My sled has 15000 kilometers on it. Any ideas???

Rik...[/b]

I would tend to agree with the guy that said you have lots of miles on it and compared it to a car with very high miles on it. What is the difficulty with some of you guys? Most people know especially mechanics and l happen to be one of them though l am not licensed, but you get that many miles on a 2 stroke and it is going to go any time. You are very, very fortunate to have had that much life out of your 2 stroke. As the guy earlier said there can be many different thing wrong with it. You must realize with 2 strokes anything can lean them out and blow a piston. Will will not be able to be 100% certain even when you see the pistons. It is only a good to certainly think so educated guess as to why it went down. Your carbs must be cleaned completely! every year. Get new foam filters without hesitation. Check absolutely everything like carb boots that they are not cracked right through. As the other guy said use ether and do a spray test to see if your crank seals are leaking. Don't go changing everythign and fixing everything if it doesn't need it. Your just going to be wasting money being scared about everything. Definitly replace the pistons and you don't need to go with factory ones. Get those cyl blocks checked and hones or bored as whatever is necessary. Check all your jets to make sure everything is stock and check the air screw settings. The other thing to check as well is your oil injection the lever pully where the cable is connected to is lined up as you will see tiny markings that your pumop cable lever is lined up properly. Make sure you have the proper main jets in each cyl. Many guys try to get more power out of the sled and they may not know what they are doing and wind up leaning the thing out and blowing a piston. As for miles yes most 2 stroke pistons only last about 5000 miles if that depending on how it is riden. Many guys claim to get much more than that but that is rare. I am sure some oen is going to say l don't know what l am talking about but they are wrong and that is their problem. I ahve ahd plenty of experience doing engine work etc for the last ten years on my own sleds that were 2 storke and just gave it up last year.

Motor eating foam is not good, but probably not the cause of the burnt piston. Could be though.
More likely you have a lean condition which is likely being caused by a bad crank seal or dirt in the carbs. I'm guessing you haven't cleaned the carb recently or you would have noticed the foam was starting to break down. Absolutely make sure you crabs are clean and replace the foam element.

Motor does have high miles on it, so you can't just put a new piston in it and drive. You need to check that the crank bearings and rod bearings are still good. Also verify the cylinders are still within stock specs. If they are not, you can have them bored a size bigger and put oversized pistons in it. If it was me, I'd replace the crank seals just in case while I had it apart.

Lastly. All these things cost money so you need to figure out if the cost of the repair is more then the machine is worth. Might be the case given the age/miles, but there is nothing stopping you from putting another 15,000 km on that machine.

I know exactly what is wrong! Your sled is old with a ton of miles. A 94 V-MAX 500 with 15,000 kilometers on it is toast. Thats like asking why a 1992 ford tempo with 350,000Km has a blown motor. You can't just change a piston there may be something wrong with the cylinder etc... There are many possiblities as to what the problem could be. Honestly the main problem is the sled is old. The motor probably needs to be completely rebuilt. If the air filters are old change them too. It is probably more worth while to buy a newer sled...

The clutch side is usually the first to go because of the extra heat coming from the clutch.

your sled's old? thats your answer? are you a mechanic? do you ride a sled? if so what kind?
why would you tell someone that there sled is old? that has absolutely nothing to do with it! I ride a 1987 exciter with a 96 v max 600 in it, I have been running it for 20 years (ya no shit) 56000.0 miles + on it, I have never had the engine apart since i built it and will put it up against ANY 500-600 and will walk all over them! so dont tell a guy just cause his sled is old is the reason it blew a piston!! because it has nothing to do with it! gheesh I hate stupid people, also very rude.
basically your telling the guy to go buy a new $10.000.00 sled cuase you dont know how to diagnose it, so why even reply! your just moking the poor guy and waisting his time, cause you can afford to be stupid!